1. Field of the Invention
Aspects of the present invention relate to a video playback apparatus and a method for controlling the same, and more particularly to an apparatus and method for controlling individual display windows when displaying different video streams on a display via individual display windows.
2. Description of the Related Art
A Picture-In-Picture (PIP) mode and a Picture-Out-Picture (POP) mode have been widely used to simultaneously reproduce different video streams on an entire screen of a display, such that the individual video streams are displayed on individual display windows, respectively.
FIGS. 1A and 1B show characteristics of a conventional PIP-based display screen. FIGS. 2A, 2B, and 2C show characteristics of a conventional POP-based display screen.
The PIP mode shown in FIG. 1A sets an entire screen 102 to a main display window 104, displays an image of a main-video stream on the main display window 104, constructs a sub-display window 106 smaller than the main display window 104 in the main display window 104, and displays an image of a sub-video stream on the sub-display window 106.
In contrast, the POP mode shown in FIG. 2A constructs a main-display window 204 and a sub-display window 206 in an entire screen 202 of a display and displays different video stream images on individual display windows 204 and 206, respectively.
A television (TV) can allow a user to simultaneously view broadcast programs received via different broadcast channels using the PIP mode or the POP mode. For example, the user can view a specific show-program via the main-display window, and at the same time can view a sports game of another channel via the sub-display window.
For another example, when video content data stored in a storage medium is reproduced and displayed, the image of the main-video stream including main contents is displayed on the main-display window, and the image of the sub-video stream including auxiliary information associated with the main contents is displayed on the sub-display window. In this case, the display method of the above-mentioned images is set to either one of the PIP mode, the POP mode, and other display modes according to setup information contained in reproduction control information contained in the content data. The reproduction control information includes a reproduction sequence of video streams, window size information, and window location information, etc.
In this manner, the main-video stream and the sub-video stream, which are simultaneously and asynchronously reproduced on a single display, are reproduced at the same time, but they may have different reproduction lengths, such that the reproduction of the sub-video stream may be firstly terminated, or the reproduction of the main-video stream may be firstly terminated.
As can be seen from FIGS. 1B, 2B, and 2C, if one of the main-video stream and the sub-video stream is completely reproduced, and new reproduction control information for changing size- and location-information of display windows of individual video streams is not received, the PIP mode continuously displays the sub-video stream image on a small-sized sub-display window although the reproduction of the main-video stream has been first terminated (See FIGS. 1B and 2C), or the POP mode allows the sub-display window to be empty in an entire screen 202, and at the same time allows the main-display window to be kept in a conventional size smaller than the entire screen 202 although the reproduction of the sub-video stream has been first reproduced (See FIG. 2B).